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LibTextCodec: Implement iso-2022-jp encoder

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Implements the `iso-2022-jp` encoder, as specified by
https://encoding.spec.whatwg.org/#iso-2022-jp-encoder
This commit is contained in:
BenJilks 2024-08-06 11:06:05 +01:00 committed by Tim Ledbetter
parent 08a8d67a5b
commit 0ca5675d59
Notes: github-actions[bot] 2024-08-08 16:50:57 +00:00 
Author: https://github.com/BenJilks
Commit: https://github.com/LadybirdBrowser/ladybird/commit/0ca5675d59d
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/975
Reviewed-by: https://github.com/shannonbooth
Reviewed-by: https://github.com/skyrising
Reviewed-by: https://github.com/tcl3 ✅
5 changed files with 255 additions and 61 deletions
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1
Meta/Lagom/Tools/CodeGenerators/LibTextCodec/GenerateEncodingIndexes.cpp
View file

@ -272,6 +272,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
{ "jis0212"sv, prepare_table(data.get("jis0212"sv)->as_array(), GenerateAccessor::Yes) },
{ "euc_kr"sv, prepare_table(data.get("euc-kr"sv)->as_array(), GenerateAccessor::Yes, GenerateInverseAccessor::Yes) },
{ "ibm866"sv, prepare_table(data.get("ibm866"sv)->as_array()) },
{ "iso_2022_jp_katakana"sv, prepare_table(data.get("iso-2022-jp-katakana"sv)->as_array(), GenerateAccessor::Yes) },
{ "iso_8859_2"sv, prepare_table(data.get("iso-8859-2"sv)->as_array()) },
{ "iso_8859_3"sv, prepare_table(data.get("iso-8859-3"sv)->as_array()) },
{ "iso_8859_4"sv, prepare_table(data.get("iso-8859-4"sv)->as_array()) },

73
Tests/LibTextCodec/TestTextEncoders.cpp
View file

@ -14,9 +14,10 @@ TEST_CASE(test_utf8_encode)
auto test_string = "\U0001F600"sv;
Vector<u8> processed_bytes;
MUST(encoder.process(Utf8View(test_string), [&](u8 byte) {
return processed_bytes.try_append(byte);
}));
MUST(encoder.process(
Utf8View(test_string),
[&](u8 byte) { return processed_bytes.try_append(byte); },
[&](u32) -> ErrorOr<void> { EXPECT(false); return {}; }));
EXPECT(processed_bytes.size() == 4);
EXPECT(processed_bytes[0] == 0xF0);
EXPECT(processed_bytes[1] == 0x9F);
@ -33,9 +34,10 @@ TEST_CASE(test_euc_jp_encoder)
auto test_string = "\U000000A5\U00003088\U000030C4"sv;
Vector<u8> processed_bytes;
MUST(encoder.process(Utf8View(test_string), [&](u8 byte) {
return processed_bytes.try_append(byte);
}));
MUST(encoder.process(
Utf8View(test_string),
[&](u8 byte) { return processed_bytes.try_append(byte); },
[&](u32) -> ErrorOr<void> { EXPECT(false); return {}; }));
EXPECT(processed_bytes.size() == 5);
EXPECT(processed_bytes[0] == 0x5C);
EXPECT(processed_bytes[1] == 0xA4);
@ -44,6 +46,36 @@ TEST_CASE(test_euc_jp_encoder)
EXPECT(processed_bytes[4] == 0xC4);
}
TEST_CASE(test_iso_2022_jp_encoder)
{
TextCodec::ISO2022JPEncoder encoder;
// U+A5 Yen Sign
// U+3088 Hiragana Letter Yo
// U+30C4 Katakana Letter Tu
auto test_string = "\U000000A5\U00003088\U000030C4"sv;
Vector<u8> processed_bytes;
MUST(encoder.process(
Utf8View(test_string),
[&](u8 byte) { return processed_bytes.try_append(byte); },
[&](u32) -> ErrorOr<void> { EXPECT(false); return {}; }));
EXPECT(processed_bytes.size() == 14);
EXPECT(processed_bytes[0] == 0x1B);
EXPECT(processed_bytes[1] == 0x28);
EXPECT(processed_bytes[2] == 0x4A);
EXPECT(processed_bytes[3] == 0x5C);
EXPECT(processed_bytes[4] == 0x1B);
EXPECT(processed_bytes[5] == 0x24);
EXPECT(processed_bytes[6] == 0x42);
EXPECT(processed_bytes[7] == 0x24);
EXPECT(processed_bytes[8] == 0x68);
EXPECT(processed_bytes[9] == 0x25);
EXPECT(processed_bytes[10] == 0x44);
EXPECT(processed_bytes[11] == 0x1B);
EXPECT(processed_bytes[12] == 0x28);
EXPECT(processed_bytes[13] == 0x42);
}
TEST_CASE(test_shift_jis_encoder)
{
TextCodec::ShiftJISEncoder encoder;
@ -53,9 +85,10 @@ TEST_CASE(test_shift_jis_encoder)
auto test_string = "\U000000A5\U00003088\U000030C4"sv;
Vector<u8> processed_bytes;
MUST(encoder.process(Utf8View(test_string), [&](u8 byte) {
return processed_bytes.try_append(byte);
}));
MUST(encoder.process(
Utf8View(test_string),
[&](u8 byte) { return processed_bytes.try_append(byte); },
[&](u32) -> ErrorOr<void> { EXPECT(false); return {}; }));
EXPECT(processed_bytes.size() == 5);
EXPECT(processed_bytes[0] == 0x5C);
EXPECT(processed_bytes[1] == 0x82);
@ -72,9 +105,10 @@ TEST_CASE(test_euc_kr_encoder)
auto test_string = "\U0000B29F\U00007C97"sv;
Vector<u8> processed_bytes;
MUST(encoder.process(Utf8View(test_string), [&](u8 byte) {
return processed_bytes.try_append(byte);
}));
MUST(encoder.process(
Utf8View(test_string),
[&](u8 byte) { return processed_bytes.try_append(byte); },
[&](u32) -> ErrorOr<void> { EXPECT(false); return {}; }));
EXPECT(processed_bytes.size() == 4);
EXPECT(processed_bytes[0] == 0x88);
EXPECT(processed_bytes[1] == 0x6B);
@ -90,9 +124,10 @@ TEST_CASE(test_big5_encoder)
auto test_string = "\U000000A7\U000070D7"sv;
Vector<u8> processed_bytes;
MUST(encoder.process(Utf8View(test_string), [&](u8 byte) {
return processed_bytes.try_append(byte);
}));
MUST(encoder.process(
Utf8View(test_string),
[&](u8 byte) { return processed_bytes.try_append(byte); },
[&](u32) -> ErrorOr<void> { EXPECT(false); return {}; }));
EXPECT(processed_bytes.size() == 4);
EXPECT(processed_bytes[0] == 0xA1);
EXPECT(processed_bytes[1] == 0xB1);
@ -108,10 +143,10 @@ TEST_CASE(test_gb18030_encoder)
auto test_string = "\U000020AC\U0000E4C5"sv;
Vector<u8> processed_bytes;
MUST(encoder.process(Utf8View(test_string), [&](u8 byte) {
return processed_bytes.try_append(byte);
}));
MUST(encoder.process(
Utf8View(test_string),
[&](u8 byte) { return processed_bytes.try_append(byte); },
[&](u32) -> ErrorOr<void> { EXPECT(false); return {}; }));
EXPECT(processed_bytes.size() == 4);
EXPECT(processed_bytes[0] == 0xA2);
EXPECT(processed_bytes[1] == 0xE3);

157
Userland/Libraries/LibTextCodec/Encoder.cpp
View file

@ -19,6 +19,7 @@ GB18030Encoder s_gb18030_encoder;
GB18030Encoder s_gbk_encoder(GB18030Encoder::IsGBK::Yes);
Big5Encoder s_big5_encoder;
EUCJPEncoder s_euc_jp_encoder;
ISO2022JPEncoder s_iso_2022_jp_encoder;
ShiftJISEncoder s_shift_jis_encoder;
EUCKREncoder s_euc_kr_encoder;
}
@ -31,6 +32,8 @@ Optional<Encoder&> encoder_for_exact_name(StringView encoding)
return s_big5_encoder;
if (encoding.equals_ignoring_ascii_case("euc-jp"sv))
return s_euc_jp_encoder;
if (encoding.equals_ignoring_ascii_case("iso-2022-jp"sv))
return s_iso_2022_jp_encoder;
if (encoding.equals_ignoring_ascii_case("shift_jis"sv))
return s_shift_jis_encoder;
if (encoding.equals_ignoring_ascii_case("euc-kr"sv))
@ -50,7 +53,7 @@ Optional<Encoder&> encoder_for(StringView label)
}
// https://encoding.spec.whatwg.org/#utf-8-encoder
ErrorOr<void> UTF8Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte)
ErrorOr<void> UTF8Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)>)
{
ReadonlyBytes bytes { input.bytes(), input.byte_length() };
for (auto byte : bytes)
@ -59,7 +62,7 @@ ErrorOr<void> UTF8Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> o
}
// https://encoding.spec.whatwg.org/#euc-jp-encoder
ErrorOr<void> EUCJPEncoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte)
ErrorOr<void> EUCJPEncoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error)
{
for (auto item : input) {
// 1. If code point is end-of-queue, return finished.
@ -98,7 +101,7 @@ ErrorOr<void> EUCJPEncoder::process(Utf8View input, Function<ErrorOr<void>(u8)>
// 8. If pointer is null, return error with code point.
if (!pointer.has_value()) {
// TODO: Report error.
TRY(on_error(item));
continue;
}
@ -116,6 +119,136 @@ ErrorOr<void> EUCJPEncoder::process(Utf8View input, Function<ErrorOr<void>(u8)>
return {};
}
// https://encoding.spec.whatwg.org/#iso-2022-jp-encoder
ErrorOr<ISO2022JPEncoder::State> ISO2022JPEncoder::process_item(u32 item, State state, Function<ErrorOr<void>(u8)>& on_byte, Function<ErrorOr<void>(u32)>& on_error)
{
// 3. If ISO-2022-JP encoder state is ASCII or Roman, and code point is U+000E, U+000F, or U+001B, return error with U+FFFD.
if (state == State::ASCII || state == State::Roman) {
if (item == 0x000E || item == 0x000F || item == 0x001B) {
TRY(on_error(0xFFFD));
return state;
}
}
// 4. If ISO-2022-JP encoder state is ASCII and code point is an ASCII code point, return a byte whose value is code point.
if (state == State::ASCII && is_ascii(item)) {
TRY(on_byte(static_cast<u8>(item)));
return state;
}
// 5. If ISO-2022-JP encoder state is Roman and code point is an ASCII code point, excluding U+005C and U+007E, or is U+00A5 or U+203E, then:
if (state == State::Roman && ((is_ascii(item) && item != 0x005C && item != 0x007E) || (item == 0x00A5 || item == 0x203E))) {
// 1. If code point is an ASCII code point, return a byte whose value is code point.
if (is_ascii(item)) {
TRY(on_byte(static_cast<u8>(item)));
return state;
}
// 2. If code point is U+00A5, return byte 0x5C.
if (item == 0x00A5) {
TRY(on_byte(0x5C));
return state;
}
// 3. If code point is U+203E, return byte 0x7E.
if (item == 0x203E) {
TRY(on_byte(0x7E));
return state;
}
}
// 6. If code point is an ASCII code point, and ISO-2022-JP encoder state is not ASCII, restore code point to ioQueue, set
// ISO-2022-JP encoder state to ASCII, and return three bytes 0x1B 0x28 0x42.
if (is_ascii(item) && state != State::ASCII) {
TRY(on_byte(0x1B));
TRY(on_byte(0x28));
TRY(on_byte(0x42));
return process_item(item, State::ASCII, on_byte, on_error);
}
// 7. If code point is either U+00A5 or U+203E, and ISO-2022-JP encoder state is not Roman, restore code point to ioQueue,
// set ISO-2022-JP encoder state to Roman, and return three bytes 0x1B 0x28 0x4A.
if ((item == 0x00A5 || item == 0x203E) && state != State::Roman) {
TRY(on_byte(0x1B));
TRY(on_byte(0x28));
TRY(on_byte(0x4A));
return process_item(item, State::Roman, on_byte, on_error);
}
// 8. If code point is U+2212, set it to U+FF0D.
if (item == 0x2212)
item = 0xFF0D;
// 9. If code point is in the range U+FF61 to U+FF9F, inclusive, set it to the index code point for code point − 0xFF61
// in index ISO-2022-JP katakana.
if (item >= 0xFF61 && item <= 0xFF9F) {
item = *index_iso_2022_jp_katakana_code_point(item - 0xFF61);
}
// 10. Let pointer be the index pointer for code point in index jis0208.
auto pointer = code_point_jis0208_index(item);
// 11. If pointer is null, then:
if (!pointer.has_value()) {
// 1. If ISO-2022-JP encoder state is jis0208, then restore code point to ioQueue, set ISO-2022-JP encoder state to
// ASCII, and return three bytes 0x1B 0x28 0x42.
if (state == State::jis0208) {
TRY(on_byte(0x1B));
TRY(on_byte(0x28));
TRY(on_byte(0x4A));
return process_item(item, State::ASCII, on_byte, on_error);
}
// 2. Return error with code point.
TRY(on_error(item));
return state;
}
// 12. If ISO-2022-JP encoder state is not jis0208, restore code point to ioQueue, set ISO-2022-JP encoder state to
// jis0208, and return three bytes 0x1B 0x24 0x42.
if (state != State::jis0208) {
TRY(on_byte(0x1B));
TRY(on_byte(0x24));
TRY(on_byte(0x42));
return process_item(item, State::jis0208, on_byte, on_error);
}
// 13. Let lead be pointer / 94 + 0x21.
auto lead = *pointer / 94 + 0x21;
// 14. Let trail be pointer % 94 + 0x21.
auto trail = *pointer % 94 + 0x21;
// 15. Return two bytes whose values are lead and trail.
TRY(on_byte(static_cast<u8>(lead)));
TRY(on_byte(static_cast<u8>(trail)));
return state;
}
// https://encoding.spec.whatwg.org/#iso-2022-jp-encoder
ErrorOr<void> ISO2022JPEncoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error)
{
// ISO-2022-JP’s encoder has an associated ISO-2022-JP encoder state which is ASCII, Roman, or jis0208 (initially ASCII).
auto state = State::ASCII;
for (u32 item : input) {
state = TRY(process_item(item, state, on_byte, on_error));
}
// 1. If code point is end-of-queue and ISO-2022-JP encoder state is not ASCII, set ISO-2022-JP
// encoder state to ASCII, and return three bytes 0x1B 0x28 0x42.
if (state != State::ASCII) {
state = State::ASCII;
TRY(on_byte(0x1B));
TRY(on_byte(0x28));
TRY(on_byte(0x42));
return {};
}
// 2. If code point is end-of-queue and ISO-2022-JP encoder state is ASCII, return finished.
return {};
}
static Optional<u32> code_point_jis0208_index_skipping_range(u32 code_point, u32 skip_from, u32 skip_to)
{
VERIFY(skip_to >= skip_from);
@ -141,7 +274,7 @@ static Optional<u32> index_shift_jis_pointer(u32 code_point)
}
// https://encoding.spec.whatwg.org/#shift_jis-encoder
ErrorOr<void> ShiftJISEncoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte)
ErrorOr<void> ShiftJISEncoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error)
{
for (u32 item : input) {
// 1. If code point is end-of-queue, return finished.
@ -179,7 +312,7 @@ ErrorOr<void> ShiftJISEncoder::process(Utf8View input, Function<ErrorOr<void>(u8
// 8. If pointer is null, return error with code point.
if (!pointer.has_value()) {
// TODO: Report error.
TRY(on_error(item));
continue;
}
@ -208,7 +341,7 @@ ErrorOr<void> ShiftJISEncoder::process(Utf8View input, Function<ErrorOr<void>(u8
}
// https://encoding.spec.whatwg.org/#euc-kr-encoder
ErrorOr<void> EUCKREncoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte)
ErrorOr<void> EUCKREncoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error)
{
for (u32 item : input) {
// 1. If code point is end-of-queue, return finished.
@ -224,7 +357,7 @@ ErrorOr<void> EUCKREncoder::process(Utf8View input, Function<ErrorOr<void>(u8)>
// 4. If pointer is null, return error with code point.
if (!pointer.has_value()) {
// TODO: Report error.
TRY(on_error(item));
continue;
}
@ -269,7 +402,7 @@ static Optional<u32> index_big5_pointer(u32 code_point)
}
// https://encoding.spec.whatwg.org/#big5-encoder
ErrorOr<void> Big5Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte)
ErrorOr<void> Big5Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error)
{
for (u32 item : input) {
// 1. If code point is end-of-queue, return finished.
@ -285,7 +418,7 @@ ErrorOr<void> Big5Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> o
// 4. If pointer is null, return error with code point.
if (!pointer.has_value()) {
// TODO: Report error.
TRY(on_error(item));
continue;
}
@ -334,7 +467,7 @@ GB18030Encoder::GB18030Encoder(IsGBK is_gbk)
}
// https://encoding.spec.whatwg.org/#gb18030-encoder
ErrorOr<void> GB18030Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte)
ErrorOr<void> GB18030Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error)
{
bool gbk = (m_is_gbk == IsGBK::Yes);
@ -349,7 +482,7 @@ ErrorOr<void> GB18030Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)
// 3. If code point is U+E5E5, return error with code point.
if (item == 0xE5E5) {
// TODO: Report error.
TRY(on_error(item));
continue;
}
@ -383,7 +516,7 @@ ErrorOr<void> GB18030Encoder::process(Utf8View input, Function<ErrorOr<void>(u8)
// 7. If is GBK is true, return error with code point.
if (gbk) {
// TODO: Report error.
TRY(on_error(item));
continue;
}

28
Userland/Libraries/LibTextCodec/Encoder.h
View file

@ -13,7 +13,7 @@ namespace TextCodec {
class Encoder {
public:
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte) = 0;
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) = 0;
protected:
virtual ~Encoder() = default;
@ -21,27 +21,41 @@ protected:
class UTF8Encoder final : public Encoder {
public:
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte) override;
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) override;
};
class EUCJPEncoder final : public Encoder {
public:
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte) override;
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) override;
};
class ISO2022JPEncoder final : public Encoder {
public:
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) override;
private:
enum class State {
ASCII,
Roman,
jis0208,
};
ErrorOr<State> process_item(u32 item, State, Function<ErrorOr<void>(u8)>& on_byte, Function<ErrorOr<void>(u32)>& on_error);
};
class ShiftJISEncoder final : public Encoder {
public:
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte) override;
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) override;
};
class EUCKREncoder final : public Encoder {
public:
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte) override;
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) override;
};
class Big5Encoder final : public Encoder {
public:
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte) override;
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) override;
};
class GB18030Encoder final : public Encoder {
@ -53,7 +67,7 @@ public:
GB18030Encoder(IsGBK is_gbk = IsGBK::No);
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte) override;
virtual ErrorOr<void> process(Utf8View, Function<ErrorOr<void>(u8)> on_byte, Function<ErrorOr<void>(u32)> on_error) override;
private:
IsGBK m_is_gbk { IsGBK::No };

57
Userland/Libraries/LibURL/Parser.cpp
View file

@ -775,31 +775,42 @@ ErrorOr<String> Parser::percent_encode_after_encoding(TextCodec::Encoder& encode
// 1. Let encodeOutput be an empty I/O queue.
StringBuilder output;
// 3. For each byte of encodeOutput converted to a byte sequence:
TRY(encoder.process(Utf8View(input), [&](u8 byte) -> ErrorOr<void> {
// 1. If spaceAsPlus is true and byte is 0x20 (SP), then append U+002B (+) to output and continue.
if (space_as_plus && byte == ' ') {
output.append('+');
// 2. Set potentialError to the result of running encode or fail with inputQueue, encoder, and encodeOutput.
TRY(encoder.process(
Utf8View(input),
// 3. For each byte of encodeOutput converted to a byte sequence:
[&](u8 byte) -> ErrorOr<void> {
// 1. If spaceAsPlus is true and byte is 0x20 (SP), then append U+002B (+) to output and continue.
if (space_as_plus && byte == ' ') {
output.append('+');
return {};
}
// 2. Let isomorph be a code point whose value is byte’s value.
u32 isomorph = byte;
// 3. Assert: percentEncodeSet includes all non-ASCII code points.
// 4. If isomorphic is not in percentEncodeSet, then append isomorph to output.
if (!code_point_is_in_percent_encode_set(isomorph, percent_encode_set)) {
output.append_code_point(isomorph);
}
// 5. Otherwise, percent-encode byte and append the result to output.
else {
output.appendff("%{:02X}", byte);
}
return {};
}
},
// 2. Let isomorph be a code point whose value is byte’s value.
u32 isomorph = byte;
// 3. Assert: percentEncodeSet includes all non-ASCII code points.
// 4. If isomorphic is not in percentEncodeSet, then append isomorph to output.
if (!code_point_is_in_percent_encode_set(isomorph, percent_encode_set)) {
output.append_code_point(isomorph);
}
// 5. Otherwise, percent-encode byte and append the result to output.
else {
output.appendff("%{:02X}", byte);
}
return {};
}));
// 4. If potentialError is non-null, then append "%26%23", followed by the shortest sequence of ASCII digits
// representing potentialError in base ten, followed by "%3B", to output.
[&](u32 error) -> ErrorOr<void> {
output.appendff("%26%23{}%3B", error);
return {};
}));
// 6. Return output.
return output.to_string();